石墨炉原子吸收光谱中铽、镝、钬基体的背景吸收研究

THE INVESTIGATION OF THE BACKGROUND ABSORPTION OF MATRIX-Tb, Dy, Ho BY GFAAS

本文研究了石墨炉原子吸收光谱中某些稀土化合物——铽、镝、钬的氯化物和硝酸盐背景吸收的特点、来源及其消除方法。铽、镝、钬氯化物和硝酸盐的背景吸收在研究的部分波长范围内呈现双峰,并且在短波部分的吸收是严重的。铽、镝、钬氯化物背景吸收的双峰来自其氯化物和氧化物的分子蒸气,其硝酸盐背景吸收的双峰来自硝酸盐的分解产物—氧化氮和氧化物的分子蒸气。把稀土样品转变为硝酸盐进行测定,有助于减小背景吸收的干扰。

The character, source and the method——decreasing of the background absorption of rare-earth compounds such as TbCl_3,DyCl_3, HoCl_3, Tb(NO_3)_3, Dy(NO_3)_3 Ho(NO_3)_3 in the graphite furnace atomic absorption spectrometry are investigated. The background absorptions of the rare-earth compounds are shown double-peaks in the investigating partial, and the absorption is serious in the short-wave part. The double-peaks of TbCl_3, DyCl_3, HoCl_3 are come from the both molecular evaporations of themselves and their oxides. But the double-peaks of their nitrates are come from a decomposed-product NO and the molecular evaporation of their oxides. It is advantage that decreasing interference of the background absorption when these nitrates converted from rare-earth compound samples are analysed.